


Return to the Throne

by ViceRoy21



Category: Undertale (Video Game)
Genre: Sans is a badass, bad asgore, sorry to asgore fans
Language: English
Status: In-Progress
Published: 2020-07-02
Updated: 2020-08-12
Packaged: 2021-03-05 02:33:46
Rating: Not Rated
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 2
Words: 4,702
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/25037053
Author URL: https://archiveofourown.org/users/ViceRoy21/pseuds/ViceRoy21
Summary: Sans is determined to right a wrong that has been left to fester for a long time, he now has the opportunity to do so.
Comments: 2
Kudos: 7





	1. Chapter 1

Sans watched the sun as it set on the horizon, the orange ball of fire signaling the end to the day. The sight once filled him with hope, that the dawn of a new future was just around the corner. Now it just mocked him, telling him that this hope was nothing more than an unattainable dream. He couldn’t remember when that hope had been crushed, probably after the 30 th reset or somewhere around there. Now all he felt was a numb indifference at the sight. 

He heard a soft set of steps making their way over to him, he knew who they belonged to without even looking back. “Coming to tell me when the next reset is? How nice of you, I usually get a little nauseous when you reset without warning” Sans said absently “How many resets does this make? 100? 200? At this point I’ve lost count”. Nothing answered him at first; the only sound was that of the monsters not too far away from them.

“You know… when I started this, every new possibility excited me, made me look forward to the next reset” a soft voice spoke to the skeleton “now though… I think I’ve witnessed every possible outcome many times over… it’s become rather lackluster”.

Sans didn’t offer a reply to the human’s words, it wasn’t worth the effort to muster up the ability to care.

“Because of that… my determination is kind of starting to fade… and with it…” Frisk started to say but stopped, taking a few more steps beside the skeleton. With a wave of their hand their menu appeared, showing the reset and load buttons. Sans cast an uninterested glance at the child, his eye lights glancing over the screen. “This was my last run, Sans” Frisk told him, gesturing to the reset button. The button had many cracks running through it, looking as if it would fall apart at any moment “As of this moment on there won’t be any more resets…”.

The skeletons eye lights flickered out and his empty sockets stared long and hard at the broken button “is this some kind of joke? Cause it ain’t funny pal”.

“I know you probably won’t believe me, I don’t blame you” Frisk said as they banished the screen “I just wanted to tell you so you can stop looking over your shoulder, waiting for the next reset. Despite what you think I do care about everyone, including you Sans; enjoy your future”. With those words Frisk went back to the group, Sans never taking his eye sockets off the child. He thought long and hard on this new revelation, his mind working overtime to figure out the human’s angle. Briefly he flicked his glance over to Papyrus and studied him a bit; watching him laugh with Undyne and Alphys.

“Enjoy the future huh?” He murmured as his eye lights came back. If what the brat said was true then maybe he could finally right a wrong that had been committed a long time ago, a time before the humans were ever a problem. And if the human was lying well it would just be one more mark on his list of “reasons to not trust the human ever”. Gathering his magic he teleported himself back over to where the other monsters stood, landing himself by the king. “Hey fluffy buns, we gotta talk” Sans told the goat monster, making the other look at him.

“Oh? Well I would be happy to have a word with you” Asgore said with a smile and followed after Sans when the skeleton took a step away, leading him out of ear shot. Once they were far enough away Asgore spoke “What is it you would like to speak about Sans?”.

For a moment Sans didn’t say anything, merely studying the king with a bland look. This caused Asgore’s smile to slowly drop and he gave the skeleton a confused look. Finally Sans spoke, his eternal grin becoming more stone like “Betcha yer really relieved, having a kid fix yer mess for you kingy”. 

“I beg your pardon? What on earth do you mean?” Asgore said with a frown.

“All I’m saying is it must be quite the relief to no longer be stuck trying to fix a big mistake that’s lasted quite a long time, I guess it ain’t as easy being king as you thought it woulda been all them years ago huh?” Sans said lightly with a shrug, Asgore stiffening “The old king musta made it look pretty simple since you wanted the job so bad you felt the need to  **kill him for it”.** Sans eye lights had extinguished, leaving his sockets empty to bore into the king.

“You don’t know what you are talking about Sans, you must be rather confused; it has been a long day, surely a nice cup of tea will help you get your skull on right” Asgore said, trying to smooth this over.

Sans eye light flared blue and yellow “You wanna know the perk of being the judge Dreemurr? Mind magic can’t affect me, gotta stay impartial and all that; but you knew that didn’t ya? That’s why you were so frustrated when no one else could take on the part of judge, a position that’s always been held by the oldest of skeletons; you wanna know why that is? The reason it’s always been us is that we can  **see right through people** ”.

Asgore frowned and stared sternly at Sans “What are you trying to accomplish from this?”.

Sans grin shifted, taking on a darker air “Nothing much, just wanting to right some wrongs. You ain’t the rightful king Asgore Dreemurr and I’m gonna make sure everybody knows… If you step down willingly and face judgement for all of your sins it would make my job a hell of a lot easier. I wonder how monster kind will react to you being the cause of the war that got them all locked away underground?”.

“No one would believe you, they don’t even remember who the previous king was” Asgore growled.

“Ya sure bout that? Cause I can name several monsters here who can back me up with a little history lesson for the masses” Sans said dryly, an eye ridge rising at the king’s defensiveness “you messed with the wrong family Dreemurr and I intend to finally put the right king on the throne”.

“Oh? And who would that king be? You?” Asgore said with a derisive snort.

Sans chuckled deeply at the king’s naivety “Me? Heavens no, I would be a terrible king; why do you think HE was on the throne? Nah, I’m talking about the true heir to the throne… You didn’t kill the ENTIRE family that night Asgore,  **I made certain of that** ”.

If he could have Asgore would have paled, a horrified look on his face as realization hit “What did you do… how did you…”.

Sans turned Asgore’s soul blue and tugged him down to Sans eye level “I’m going to make you regret killing my brother Asgore; his son WILL take his rightful place as king one way or another. If you don’t step down I’m gonna enact some old laws that  **won’t give you a choice** ”. Asgore’s eyes glanced to the side where all the other monsters stood, specifically where one skeleton laughed happily; how had he not known?

“You won’t get away with this Sans; I have too many loyal subjects for you to do this without negative repercussions” Asgore warned.

“What? You thought I spent all of our time underground doing absolutely nothing?” Sans scoffed “You should really pay closer attention to your  **subjects** Fluffy buns; you get 24 hours to bring to light your crimes or I’ll be forced to do it myself”. With that said Sans released his hold on the goat king and his eye lights returned. He walked his way over to Papyrus, his smile becoming relaxed as the taller turned to look at him. Asgore watched him walk away, a grim look on his face as the skeleton brothers walked off to enjoy their first night on the surface together.


	2. Chapter 2

**Notes for the Chapter:**

> oi vey this chapter. it took me a lot of editing and re-editing and hair pulling but I managed to pull it together. why the hell don't i ever plot out these stories? I just slap the idea down and then cuss myself out a lot XO

Sans and Papyrus had a great time taking in the sights, exploring all the human city had to offer. Despite reservations of how the humans would react, things went surprisingly well for the monsters and they were greeted with a lot less hesitation and hostility than many had expected. So for the time being monsters were staying in a camping area set up for them on the outskirts of the city until housing could be established for the residence of Mt Ebott. 

Once everything had settled down and he was sure Papyrus was taken care of, Sans had gone about putting together what was needed for his plan to be made a success. This meant he had to put the finishing touches to his machine that until now had remained sitting in his lab. Being on the surface allowed him access to the crucial parts that he had been missing. If he was going to reclaim the throne from Asgore with the least amount of resistance possible from the people he would need to bring in some reinforcements, starting with an old friend.

While Sans was working on this, Asgore was busy trying to figure out a way to stop Sans from ruining everything for him. His top priority was getting rid of the skeletons, with them gone his position as king would remain untested. But the question was how to go about doing so? He didn’t want to spark another war, that would just end up with them in the mountain again and with the two of them having so many friends just simply making them disappear was not an option.

In the blink of an eye 24 hours had passed. Despite not knowing what was going on, the other monsters could feel a tension in the air. Something important was going to happen soon and it had everyone on their guard despite not knowing what. Asgore was quite twitchy, constantly looking over his shoulder. He had no doubt Sans would make true on his word but he refused to air any of his secrets to the monsters he ruled over, consequences be damned.

A ripple shifted through the air, catching all the monster's attention including Asgore. In a clearing at the center of the camp a large cloth covered thing appeared with a cloaked figure stood beside it. Monsters quickly gathered in a circle around the mysterious appearances, eager to figure out exactly what was hidden beneath. Asgore frowned and pushed his way to the front of the murmuring crowd. As soon as he was in the hooded figure's sight they marched purposefully towards the boss monster, all the others backing up to give the two some room.

“Hello friend, would you please state your purpose for bringing… whatever this is into our camp? However did you get it here?” Asgore asked politely despite his wanting to go on the offensive, this figure unnerved him greatly despite them being so much smaller than him. The being reached up and removed their hood, revealing Sans grinning face and making Asgore tense.

“Sup bud, it’s been 24 hours like I said” Sans informed him, a blue and yellow flicker in his eye light “you gonna cooperate?”. The murmurs grew louder in surprise and there was a commotion at the back as a few specific monsters tried to make their way to the front to see the commotion.

Asgore’s face hardened as he said “Are you certain now is really the time for this and in front of so many people?”.

“Well, it doesn't make any sense to do this in private if we are going to be moving things along” Sans said with a lazy shrug “So what is it gonna be? You gonna speak up or should I? Cause I got some really great motivation just waiting to have a word”.

The group of monsters finally pushed their way to the front and took in the sight before them. “Ah, brother! I’ve been looking everywhere for you” Papyrus said happily, not noticing the tension. 

Sans gave his brother a wave and a lazy grin “Sorry bro, I had some business to take care of; All I need is some confirmation from ol’ fluffy buns and I can get things rolling”.

Asgore’s eye twitched and he leaned forward, lowering his voice so that it was just between the two of them “What you are asking would end everything we are working to establish, would you really ruin this for everyone? Are you really so selfish?”.

Sans turned his sockets back on Asgore, the lights disappearing and he spoke lowly to match the king “Selfish? I have sacrificed everything for those I care about, not once have I ever asked for anything, taken anything for myself, even now I want nothing more than to rip you to shreds… but I won’t, because I care about those I love, the ones I would be hurting with my rash actions… you are the selfish one Asgore Dreemurr and I plan to put an end to it. You have one last chance before I lose my patience”.

Asgore growled, his lips pulling into a sneer “Do your worst little skeleton, what you have to say will cause no harm to me”.

A low chuckle came from Sans as he took a step back, his eye lights flickering back into existence with a wicked glint behind them. Turning to the crowd, he cleared his throat and began to speak out loud. “Hello my friends, you all know me as Sans the skeleton” He began “I have a very important question for every monster here, who remembers the time before the war between monster and human?”. 

A few hands lifted at Sans question, Gerson and Toriel being among them. Sans nodded, as if he knew how many would remember even if just barely “Next question, who here knows of the previous royal family, before the Dreemurrs rose to the throne?”. Those same few hands stayed up, none rising to join them. A lot of confused murmuring went up among the crowd, wondering where this line of question was going.

“I think it’s time for a little history lesson for the younger generation who don’t know. Before Asgore Dreemurr claimed the throne, a skeleton ruled monster kind. He was wise, fair, and compassionate” Sans spoke “he was loved by all races, including the humans. He had a family, an older brother, a wife, and a child… One night the Serif family were all murdered in their sleep”.

Gasps rang among the crowd of monsters. Sans nodded in agreement with their thoughts about the fate of the royal family then continued speaking “no one knew who had killed the beloved royal family and without a king on the throne, everything was in chaos. It wasn’t long before Asgore stepped up and declared himself as the new king; with the state of things no one contested his claim. Soon it was declared that a human had slain the royal family and monsters claimed humans as their enemies. War broke out between monsters and humans, war monsters were not prepared for nor were they capable of winning which led to our fate under the mountain”.

There were many cries of outrage, monsters wondering why they should cooperate with humans if they were just going to do such things. Asgore tried to placate the crowd before they could form a mob to take out their anger. Sans let this continue for a little longer before summoning a blaster and shooting it up into the sky to gain every monster's attention. They all quieted at the display of power, Papyrus mouth falling open at the sight.

Sans cleared his throat and spoke “before you all decide to create a lynch mob perhaps you should listen to the rest of my story hm? Now, I’m about to tell you all something that no one else knows. It is a closely guarded secret so listen carefully. You all remember how the king had a brother right? Well this brother had a very important job. Being the oldest living skeleton, it was his duty to be the judge for the king, anyone caught in the middle of a criminal action would be brought before the judge. Their sins would be laid bare before him and he would decide their fate. No one who stood before this skeleton’s eye could hide their secrets and intentions. 

This fact brings me to the next part of our tale, a tale only a handful know. The judge had heard plots to do away with the royal family, something he had brought to the king and queen’s attention as soon as he was aware of them. This put a heavy burden on their shoulders. The king knew he could not abandon his people by fleeing to save his own life and to send his family away would alert their assailants that their plans had been discovered. The king and queen both agreed that they could not leave but to stay would almost certainly be the end of them. There was only one hope for this family, the young prince.

The king made his brother swear an oath. He would do everything in his power to protect the child, no matter the cost. Unable to say no, the judge swore this oath; even if it cost his brother’s life, he would protect his nephew till his last breath. After this the king and queen went on, pretending nothing had occurred… They died that very night. The judge, feeling uneasy, had gone to check on his family. That same feeling told him to stay out of sight. Before his eyes the king and queen were dusted. The judge wanted nothing more than to strike the attacker dead but his oath to his brother stayed his hand, his nephew was priority number one.

He fled the room using a special ability of his, an ability to warp the very fabric of time and space. It took him to his nephew’s room where he scooped up the small soul, an infant that was now orphaned. In the baby’s place he scattered some monster dust he had obtained for this very reason, to make it seem as if the baby had died in his sleep. After such a thing was done he transported them away from the castle… He left to raise the baby in secret, with the hopes that he would one day reclaim the throne”. The crowd that surrounded them were so quiet you could hear a pin drop.

“Where is this prince now then if he isn’t dead? What happened to the king’s brother? And the guy who killed the royal family!” A voice spoke from the crowd, causing everyone to regain some of their senses and begin questioning the skeleton.

Sans hummed as he glanced around at the crowd, his eye lights settling on Papyrus. The taller skeleton was staring at him in curiosity and confusion. “The king's brother did just as he vowed, he raised the prince and did everything in his power to protect him… that includes hiding the prince’s true heritage from him. To this day he remains the judge even though there has been no need for him since there has been no crime in the underground. As for the one who killed the king and queen?... Well, he got exactly what he wanted”.

Sans turned back to Asgore and he narrowed his eye sockets at the taller monster “The judge is done hiding. Today he challenges Asgore Dreemurr to his claim to the throne; it’s time to crown the true heir as king”.

An uproar went through the crowd, the monsters questioning why they should accept a random stranger as their king when Asgore was their savior. “This monster is a coward, a liar, and a murderer” Sans declared, a boney finger pointed directly at Asgore “He is the murderer of the royal family and usurper of the crown!”.

“Papyrus, what is your crazy brother doing” Undyne hissed to her best friend, outraged by Sans claims. Papyrus shook his head in confusion and denial, his brother’s motives a mystery even to himself.

“I was there all of those years ago, I witnessed the murder of my brother, king Papyrus Serif the second!” Sans hissed, his eye flaring bright blue and yellow “I, Comic Sans Serif under the ancient laws of monster kind, challenge the criminal Asgore Dreemurr for the throne in the name of prince Papyrus Serif the third! Accept my challenge Dreemurr or accept the charges laid against you”. A stunned quiet fell over the crowd, all monsters waiting to see what their king would do, would he accept the skeletons challenge or would he accept the label of murderer and fraud. Asgore looked around himself at all the monsters watching and he growled lowly under his breath before returning his gaze to Sans.

“Very well skeleton. I, king Asgore Dreemurr, accept your challenge. Should I win you are to leave and never return, agreed?” Asgore said, sending shocked murmurs through the crowd.

Sans gave him a lazy grin “I can live with that”.

Sans turned back towards the large covered object behind him, his cloak swishing around him dramatically and falling away to reveal what he wore underneath. It was his old uniform from long ago when his brother was still alive. The monsters around him murmured curiously at the sight of him, it was strange to see sans wearing anything other than his jacket, shorts, and slippers.

Sans gripped the cloth and tore it away from the machine, revealing his invention to everyone and receiving many mixed reactions. “I’ve been working on this thing for a long time” Sans told them as he patted the doorway “ever since Gaster fell into the core I’ve been working on a way to bring him back but with how limited our supplies were I had to give up and leave it sitting in my lab; now that we are on the surface though I managed to get everything I need to complete it”.

“Who is Gaster?” Toriel asked, she hadn’t spoken a word since this had all begun because she had always had a suspicion that Asgore was hiding something from her even before they were married.

“I’m glad you asked” Sans said as he started punching keys on the display “W.D. Gaster was the royal scientist as well as the prince’s personal bodyguard, he is the monster who created the core. No one remembers him because when he fell into the core his essence was ripped apart and scattered across time and space… until now, with this machine I have created a way to reverse what happened to him and return him fully back to our reality”.

“B-but how d-do y-you r-remember him th-then?” Alphys asked in confusion.

“I haven’t a clue Alph” Sans shrugged and this caused Alphys to sigh in disappointment.

The machine started to whir to life and began to flash brightly. The monsters had to shield their eyes as the lights grew brighter and started flashing faster. Suddenly everything stopped flashing and everyone rubbed their eyes to clear the spots away.

Smoke poured from the machine as the door slowly opened and a figure stepped out. Many murmurs rippled through the crowd and several gasps could be heard as memories returned to those who knew Gaster. If Asgor wasn’t covered in white fur he would have visibly paled as memories of this skeleton flooded his mind as well as memories of just how he had fallen into the core.

Gaster blinked his eyelights around himself, confusion and surprise all over his features. Sans smiled a true happy smile for the first time in many years “Welcome back old friend”.

Gaster settled his eyelights on Sans and they flashed in recognition “Sans? What is going on? I remember doing an inspection of the core and then… darkness”.

A tear formed in Sans socket and he stepped forward to pull the other monster into a hug “you’ve been gone a long time bud… I’ll explain everything later but right now all you need to know is we’re back on the surface and I’ve finally exposed Dreemurr, I’m finally putting the right king on the throne Dings”.

Gaster gasped as he stared down at Sans and placed his hands on the other’s shoulder “But the prince-”.

Sans lifted his head and gave him another grin “I told you, you’ve been gone a long time”. Sans pointed over at Papyrus and Gaster followed the finger. Another gasp left him as his eyelights landed on Papyrus who was still watching on with so much confusion. 

“He looks just like the king” Gaster whispered as he stared in wonder.

“Acts like him too” Sans chuckled as he finally pulled away from the hug and turned towards Papyrus “Hey Pap’s come say hello to an old friend of mine”.

Papyrus let out a small Nyeh and walked up to the two of them “The great Papyrus is so confused as to what is going on”.

Gaster choked up a little at hearing the other speak and when Papyrus was within arms reach he pulled the young skeleton into a tight hug “You’re so much like your father!”.

All Papyrus could do was stand there in confusion and let the stranger hug him, giving him a light pat as he looked down at Sans “I’m begging you to explain things to me”.

“I will Paps, I promise, no more lies” Sans told him, finally relieved to be able to speak those words. Papyrus nodded in acceptance and continued to comfort the skeleton hugging him.

Sans glanced up as he heard someone walking over to them and saw that it was Toriel “Sup Tori”.

“Sans, might I have a word with you for a moment?” Toriel asked as she watched the reunion of the two skeletons.

“Sure” Sans told her then turned to Papyrus and Gaster “Why don’t you two go have a chat, it’s long overdue”.

Gaster pulled back as a blush crossed his skull and he cleared his throat “you are quite right Sans, I am eager to hear about everything I have missed in my absence”.

Sans watched the two walk away then turned to the machine and shut it down, throwing the sheet back over it. “Okay Tor, let’s go somewhere less crowded” Sans said as he looked around at the still gathered crowd of confused and conflicted monsters. Toriel nodded and stepped away, Sans following after her. He noticed that Asgore was nowhere to be seen, he must have slipped away while everyone was focused on Gaster’s return.

The two of them moved far enough away for them to have their private chat then stopped and turned to face each other. “I had always felt something was off with Asgore” Toriel told Sans “even during our younger years as children he had always shown an enviousness towards the king, I had assumed he would grow out of it… I’m so very sorry for what happened to your family Sans”.

“It wasn’t your fault Tor, you don’t have to be sorry” Sans told her, giving her a reassuring smile.

“I just want you to know that whatever you decide I will be behind you” Toriel told him, placing her hand on his shoulder “it is long past time for things to finally be laid to rest”.

“Thanks for the support, things are going to get rocky before they get better” he warned “most of the monsters grew up under Asgore’s rule, they aren’t going to easily accept this as fact”.

“Sadly what you say is true, it will be difficult but I have faith that everything will be alright given enough time” Toriel told him with a reassuring smile.

“I know they will be, I finally have hope for the future” he said, returning her smile with a grin of his own.


End file.
